This invention relates to improvements in rotary devices for cleaning conveyor belts.
During the handling and conveying of minerals, rock, ash and other friable materials, the inherent and created dust can cause a health hazard when the fine particles are blown into the atmosphere where it can affect the respiratory organs of people working in the immediate locality. In the case of the larger particles of dust, they can cause an environmental nuisance when they fall to the floor and obscure walkways and obstacles etc. thereby leading to accidents.
In order to overcome these forms of pollution, it is usual for the mineral to be sprayed by jets of water both before and during the early stages of transportation so that the movement and transfers of the mineral from one location to another will reduce this dust hazard to a minimum.
Where the transporting medium is a conveyor belt made of a rubber, plastic or neoprene substance, the effect of this wetting solution to overcome the dust problem, in turn creates another problem. A certain amount of the wet dust adheres to the surface of the carrying belt and is eventually taken by the return belt into the conveyor drive system of frictional rollers thereby causing the coefficient of friction to be reduced with the effect that the belting will slip and the efficiency of the conveyor will be impaired. In an endeavour to overcome this problem of belt slip, the tension of the belt may be increased but this in turn can lead to belt breakages due to the high tensions involved.
An additional problem associated with wet dust adhering to the surface of the return conveyor belt is that, as it dries out, the dust is deposited on the idler rollers and return drums of the conveyor. Should the mineral being carried by the conveyor be coal, such accumulated deposits can create an explosive situation, so requiring the employment of workmen to remove these deposits.
Where the dust is wet, these agglomerations cause the steel conveyor structure to corrode and deteriorate much faster than would have been the case if the dust had been removed. In a similar manner, the abrasive nature of many mineral dusts can reduce the working life of the conveyor belting and so increase the costs of material handling.